In order to display video on a television monitor, an electron gun inside the monitor's cathode ray tube moves across the screen line by line as it scans its way down to the bottom of the screen. Video transmission is delayed while the electron gun moves back up to the top of the tube to display the next image. During this delay, called the vertical blanking interval (“VBI”), other data may be delivered to the display. For example, closed captioning text, stock market tickers and news and weather updates are often embedded in television broadcast signals. In particular, closed caption data is typically embedded in the broadcast at line 21 of the VBI. This system allows the more data to be delivered to the television and, therefore, provides for more efficient operation.
Thanks to advances in streaming media technology, television signals can also be transmitted and viewed on the Worldwide Web. Streaming media generally includes a digitized set of images and sounds that are sent over the Internet and played for the viewer at an end user station in sequence. Significantly, the image and sounds are played as they arrive. The use of streaming media, therefore, allows an Internet user to avoid having to download an entire file before being able to play any audio or video. This often saves a substantial amount of time and eliminates considerable frustration.
While closed caption and other information is easily displayed on a television set, currently available streaming media players cannot always display such information in an Internet browser. For example, closed caption data is typically not delivered in a format that can be used by a streaming media player. More specifically, closed caption data is typically delivered as single letters or in segments of words rather than as entire words or phrases. Thus, it must be displayed by a device that can simultaneously display information that is received at different times. In contrast, audio-visual media players are set up to receive information as a stream, and to continuously replace existing data with new data as it is received. Currently available methods, therefore, cannot typically be used to display closed caption text using an audio-visual media player.